Notes:
Knights are good early on in the game because they can use the best weapons available. Also, they have Two-Handed, an ability that sacrifices the defense and evasion for double damage. Later on in the game when Dual-Wield and !Rapid Fire is available, Two-Handed becomes weaker. Still, throughout World 2, Two-Handed will be among the best physical damage you can get, only outclassed by Dual Wield Twin Lance. !Guard is also worth a mention because it is really good when combined with Counter for some bosses. The main problem is that you want to stop at Two-Handed because nothing else is worth it. Knight will probably not be a class you master and take with you for the endgame.
Monk is a very useful class. They have some of the best innate abilities, Barehanded and Counter. They cannot wear shields or weapons, and can only wear light armor. They do have high HP, but I don't prefer to keep one in the front line. The reason is that their light armor hurt them. They do very high damage, but later on, in the game their damage, which still increases, becomes less popular due to abilities such as !Rapid Fire. While being useful earlier on with !Kick, !Chakra, and high damage output, their innate abilities are what matter in the endgame.
With Theif, you can Sprint, find hidden passages, and steal rare items which greatly benefit your playing experience. Stealing is not required for anything, but if you do want to steal then you might want to change your job to a Thief instead of equipping the !Steal ability. For others such as finding passages, you can just equip Find Passages. Also, if you're hurt and need to find a town fast, then equip !Flee to escape quickly.
As with any Final Fantasy, healing magic is essential. You need at least one character specializing in the White Mage job. Two is even better! One interesting thing is that White Mage has one of the best single-target spells in the game, Holy. Its single-target damage is almost as good as Flare but for about half the cost.
Black magic is a common feature of Final Fantasy games, so there's a bias that leads players to favor Black Mages in Final Fantasy V. Black Mages are an awesome job class. Flare is great for boss battles. However, my advice is to try not to invest in them as your top casting class. This game's job system is robust and offers other strong casting classes that are worth exploring.
Blue Magic is about using enemy spells. An enemy needs to cast the spell on you for you to learn it. Hence, Blue Mage is a class that requires patience. It takes time to build up a good, useful collection of Blue Magic. I recommend using a walkthrough to help you seek the best Blue Magic and efficiently build up this job. Additionally, I recommend Beastmaster/Mediator in conjunction with Blue Mage to help speed up the process of learning Blue Magic.
Like Dragoon, Berserker is not very useful. It doesn't have a default ability because you cannot control it. You are “berserking” so your damage is randomly boosted by 25% to 50%. There is one unique use for this job. It only takes 500 ABP to master it, and it gives +21 Strength/+25 Vitality. This boost is second to Monk for best stat gains in those categories.
Mystic Knight can be useful or useless depending on your patience and preferences. Initially casting !Spellblade to activate the magic results in a round of doing nothing. This makes this job annoying for random battles since you're continually casting !Spellblade for every new battle. Another annoyance is that you can't target the magic on multiple targets. Mystic Knight is most useful for boss battles. Heavy damage can be inflicted when its abilities are used right. Drain is the most useful; it lets you heal how much damage you inflicted with your weapon.
Time Mages are a good class. They have Meteor, one of the best damaging spells in the game. They go well with White Mages while giving them an offensive spell. Hastega casts Haste on the entire party, which is very useful. Float, Teleport, and Regen are good spells for convenience.
Red Mages can use White Magic and Black Magic, but only up to level 3. This job is awesome until the middle of the game when White/Black Magic above level 3 is available to you. Until then, Red Mage allows your casters to combine with others types of magic. It pairs well with Summoner and Time Mage. The !Dualcast ability is valuable; you can learn it easily towards the end of the game to use with other casting classes.
Summoner is regarded as the best attack-magic casting job. They have both offensive and defensive summons. The catch is that every summon can only be obtained through specific side quests. If you're not talking to everyone in towns or following a walkthrough, you may miss collecting a summon beast.
Summoner spells are always multi-target, which means you do halve base power. For example, Thundara is 50 ATK and Ramuh is 53 ATK. When casting single-target, both do about the same damage. But when casting multi-target, Thundara only has 25 ATK. Summoner is much better for multi-target attacks, while Black Mage is better for single-target attacks. The final boss is multi-target, which is why Summoner is ideal.
Geomancer is a job that is useless until you need it. For example, when you're in a dungeon with pits you may want to use Geomancer for Find Pits. The Float spell is better/easier than using Light Step.
Casters might consider obtaining the !Gaia ability before they can obtain the Ranger job or if you do not want to level up Ranger for Equip Bows and/or !Rapid Fire. Damage using !Gaia depends on one's Magic, not Strength, so this is a great ability for casters. Also, it costs no MP, so you can use it over and over again. It does not do incredible damage, but it is surely better than attacking in the back row with a knife.
This class can prevent an enemy from attacking, controlling that enemy, and catching an enemy. The true gem of this class is to control an enemy then force it to use an attack on a character with the Blue Mage's Learning equipped. !Catch is not needed at all and is useless in boss fights, so no character needs to master Beastmaster but rather one should have the !Control ability.
Ninjas are slower and stronger thieves. Physically, they're stronger than Warriors while sacrificing defense. Having two less Agility than Thieves, Ninjas have fourteen more Strength and a bit more Vitality. They can't steal, but they can throw (especially shurikens) that does unbelievable damage and of course, then can attack twice while wielding two weapons.
Having a Ninja around will let you get more pre-emptive strikes and the Ninja will attack before the Warriors. If you find that they are too weak for a certain enemy, then you can put them in the back row. Since they can use special weapons, they can equip items such as Moonring Blade and not miss out on damage. They're not as useful as Thief's !Steal or Agility bonus, but they do have Dual-Wield and the ability to deal massive damage.
The Samurai's Shirahadori is an awesome innate ability! With it, you have a better chance at dodging physical attacks without wasting an ability slot. Also, !Zeninage does a huge amount of damage (but should be used sparingly such as only on bosses). !Iainuki works very well to a certain extent. While Shirahadori is a great innate skill to have, it is not worth the 820 ABP just to get it. A Summoner using Golem would already be enough against physical attacks. Therefore, I think of Samurai as only a nice class to have if you want to grind. !Zeninage is useful in certain situations.
This is not a useful job. !Jump does double damage but takes longer to execute. More importantly, while in the air, other characters (probably mages) will get targeted. Dragoon is more useful in the iOS/PC releases because the new “Twin Lance” they added allows your character to hit twice with !Jump. Twin Lance can be found early in World 2.
Dancer is a good job towards the end of the game, but it's quite restricted. You cannot make a good dancer without wearing equipment unique to dancers, which means to use the Mime class for a Dancer you will have to give up two ability slots having only one free. It's a damaging class, and whether or not you want to use !Rapid Fire or !Dance is completely up to preference.
Chemist does not offer a lot of value. Pharmacology is good if you don't have the patience to build up a White Mage. Other than that, Chemist is purely an optional class.
Bard has two good songs: Romeo's Ballad and Requiem. Romeo's Ballad is a great spell because it stops most enemies from random encounters in Worlds 1 & 2, making the game a breeze. Requiem deals massive damage if you find undead enemies. Bard, though, is not helpful for boss fights.
This class has two abilities that are valuable for making magic users more useful with physical attacks. Those abilities are EqBow and !Rapid Fire. This requires an explanation. Tactfully, it's best to have magic users in the back row so that they take less damage. But this also causes them to inflict less damage with their physical attacks. When magic users equip both EqBow and !Rapid Fire, they can shoot four arrows that never miss.
The Freelancer (the 'Normal' class in the SNES fan translation) is the default job from Final Fantasy V that has no defining characteristics. It's the default job the party starts with, and if you mastered jobs, the job your party should end with.
Freelancer begins with the ability to equip any weapon, armor, or accessory, but is otherwise the weakest job. Its main strength is that, as characters master and level up other jobs, Freelancer can equip their command abilities in their two ability slots, and gains most of their innate support abilities without needing to use up a slot for them. Therefore, Freelancer eventually becomes the most powerful job in the game, alongside the Mime.
Mimes are great! For casters, you can put up to three casting commands or two casting commands plus !Dualcast so you can cast twice per round! Either way, it's a very flexible class assuming that you have all the powerful innate abilities passed down such as Dual-Wield and Shirahadori.
The job is earned in the Merged World where the player can take the submarine south of the Phoenix Tower desert and dive to find the sunken Walse Tower. At the bottom, the player can find a shard of the Water Crystal. Defeating Famed Mimic Gogo earns the Mime job. The player has seven minutes to complete this.
Necromancer is better than Summoner and Black Mage! Not only do most of their spells inflict top-level damage, but they add additional statuses and hit all enemies. However, there's a big drawback: you get Necromancer so late in the game that it's not worth it. Dark Arts is similar to Blue Mage where you need to learn the spells from enemies, which takes a lot of time and patience.
After collecting all 12 weapons from the Sealed Castle of Kuza, Necromancer is awarded to you after defeating the optional boss, Enuo. It's one of the harder bosses in the game! You find it in the secret sea chasm.
Cannoneer is an excellent class for its !Combine ability. Note that all statuses from !Combine have a 75% chance of being inflicted. This is important to remember. For example, if you cast the Slowga spell, it takes the opponent's magic evasion and level into account, resulting in a low probability of actually inflicting Slow. However, using !Combine and Turtle Shell, not only do you deal 200 base damage to all enemies, but you have a flat 75% chance of inflicting Slow. It also costs no mana to use - it just requires items.
After collecting all 12 weapons from the Sealed Castle of Kuza, Cannoneer can be found in the secret sea chasm.
Gladiator is the only job other than Knight and Freelancer to use swords. !Finisher is the only worthwhile ability, but overall the class isn't useful.
After collecting all 12 weapons from the Sealed Castle of Kuza, Gladiator can be found in the secret sea chasm.
The Oracle is the strongest mage job, boasting the highest Magic stat. Its innate command, Condemn, is unpredictable, meaning a magic skillset should be used in its ability slot. It also learns the Predict command, which can be similarly powerful, but is equally unreliable.
After collecting all 12 weapons from the Sealed Castle of Kuza, Oracle can be found in the secret sea chasm.